In western Igboland (Anioma), the Ekumeku — often translated “the invisible, devastating whirlwind” or “don’t speak of it” — resisted the Royal Niger Company and then the colonial government for some thirty-one years. Young men (otu okorobia) from many towns took secret oaths and fought through ambushes, silent communication and surprise raids rather than pitched battles. Leaders remembered include Dunkwu Isusu, Nwabuzo Iyogolo, Awuno Ugbo, Agbambu Oshue and Idegwu Otokpoike.
The movement grew in reaction to Native Courts, imposed chiefs and missionary pressure, after British bombardments such as Ndoni (1870) and Onicha-Ado (1897). Britain was forced into a temporary settlement in 1898. Fighting flared again in 1902, 1904 and 1909; in 1904 the movement shifted to defend individual towns, and the 1909 revival began with a succession dispute in Ogwashi-Uku.